Lead(II) complexes with phosphorylthiolato and thiophosphorylthiolato ligands

Abstract

Neutral lead complexes of a series of phosphorylarenethiol and thiophosphorylarenethiol proligands have been synthesised. Compounds [Pb{2-(Ph₂P)C₆H₄S}₂] 1, [Pb{2-(Ph₂P)-6-(Me₃Si)C₆H₃S}₂] 2 and [Pb{2-(Ph₂PO)-6-(Me₃Si)C₆H₃S}₂] 3 were obtained by the electrochemical oxidation of a lead anode in a cell containing an acetonitrile solution of the ligand. [Pb{2-(Ph₂P(O)CH₂)C₆H₄S}₂] 4, [Pb{2-(Ph₂P(S)CH₂)C₆H₄S}₂] 5 and [Pb{2,6-(Ph₂P(S)CH₂)₂C₆H₃S}₂] 6 were obtained by addition of the appropriate proligand to a methanol solution of lead acetate. The molecular structures of 3, 4 and 5 show the metal in a five-coordinate geometry with the stereochemically active lone pair on Pb(II) in an equatorial position of a trigonal bipyramid. In 3, the metal coordination is supplemented by an additional weak Pb–(η⁶-C₆H₆) intermolecular interaction with a phenyl ring from a neighbouring molecule. Compound 6 consists of monomeric neutral molecules with the lead atom in a pseudo trigonal-bipyramidal geometry and additional weak intramolecular coordination with two sulfur atoms.